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Updated: Jun 3, 2026

Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Crystal structure, magnetic properties, and Mössbauer spectroscopy of new layered iron oxyselenide Nd2Fe2O3Se2
Yayoi Fuwa1, Makoto Wakeshima, Yukio Hinatsu
1Division of Chemistry, Graduate School of Science, Hokkaido University, Sapporo, Japan. y-fuwa@sci.hokudai.ac.jp
Abstract:
The crystal structure and magnetic properties of a new layered iron oxyselenide Nd(2)Fe(2)O(3)Se(2) have been investigated through powder x-ray diffraction, magnetic susceptibility, specific heat, and (57)Fe Mössbauer spectrum measurements, and electronic structure calculations. This oxyselenide crystallizes in a tetragonal structure (space group I4/mmc) which is isostructural with La(2)Fe(2)O(3)Se(2). The lattice parameters were estimated to be a = 4.0263(1) Å and c = 18.4306(2) Å by the Rietveld analysis. Through its magnetic susceptibility, specific heat, and (57)Fe Mössbauer spectrum measurements, a long-range antiferromagnetic transition of the Fe(2+) ions was found at 88 K and the Nd(3+) ions exhibited Curie paramagnetic behavior down to 2 K. Two magnetic structure models for the Fe(2+) ions were suggested from the Mössbauer spectra.
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